U.S. patent application number 14/971040 was filed with the patent office on 2016-04-07 for cutter tool insert having sensing device.
The applicant listed for this patent is Diamond Innovations, Inc.. Invention is credited to Patrick Georges Gabriel Dapsalmon, Joel Vaughn, Steven W. Webb.
Application Number | 20160097241 14/971040 |
Document ID | / |
Family ID | 47360780 |
Filed Date | 2016-04-07 |
United States Patent
Application |
20160097241 |
Kind Code |
A1 |
Vaughn; Joel ; et
al. |
April 7, 2016 |
CUTTER TOOL INSERT HAVING SENSING DEVICE
Abstract
A cutting element for an earth-boring drilling tool and its
method of making are provided. The cutting element may include a
substrate, a superhard layer, and a sensing element. The superhard
layer may be bonded to the substrate along an interface. The
superhard layer may have a working surface opposite the interface
and an outer peripheral surface. The outer peripheral surface may
extend between the working surface and the interface. The sensing
element may comprise at least a part of the superhard layer.
Inventors: |
Vaughn; Joel; (Groveport,
OH) ; Webb; Steven W.; (Woodlands, TX) ;
Dapsalmon; Patrick Georges Gabriel; (Paris, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Diamond Innovations, Inc. |
Worthington |
OH |
US |
|
|
Family ID: |
47360780 |
Appl. No.: |
14/971040 |
Filed: |
December 16, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13530073 |
Jun 21, 2012 |
9222350 |
|
|
14971040 |
|
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61499311 |
Jun 21, 2011 |
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Current U.S.
Class: |
175/39 ;
175/40 |
Current CPC
Class: |
Y10T 156/10 20150115;
E21B 10/56 20130101; E21B 47/00 20130101; E21B 10/46 20130101; E21B
47/01 20130101; E21B 10/36 20130101; E21B 12/02 20130101 |
International
Class: |
E21B 10/56 20060101
E21B010/56; E21B 47/00 20060101 E21B047/00; E21B 12/02 20060101
E21B012/02 |
Claims
1. A cutting element for an earth-boring drilling tool, comprising:
a substrate; a superhard layer bonded to the substrate along an
interface, the superhard layer having a working surface opposite
the interface and an outer peripheral surface extending between the
working surface and the interface; and a sensing element comprising
at least a part of the superhard layer.
2. The cutting element for earth-boring drilling tool of claim 1,
wherein the sensing element measures one or more parameters
selected from a group of temperature, pressure, wear, magnetic
properties, wear volume, force, acceleration, electrical
conductivity, and combinations thereof.
3. The cutting element for earth-boring drilling tool of claim 1,
wherein the sensing element comprises a sensor that is selected
from a group of temperature sensors, pyroelectric sensors,
piezoelectric sensors, magnetic sensors, acoustic sensors, optical
sensors, infrared sensors, electrodes, electrical resistance
sensors, and combinations thereof.
4. The cutting element for earth-boring drilling tool of claim 1,
further comprises transferring means for transferring output
signals from the sensing element to a circuit.
5. The cutting element for earth-boring drilling tool of claim 1,
wherein the sensing element comprises an entire superhard
layer.
6. The cutting element for earth-boring drilling tool of claim 1,
wherein the superhard layer comprises diamond.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and claims the priority benefit
of previously filed U.S. Provisional Patent Application No.
61/499,311, which was filed Jun. 21, 2011.
TECHNICAL FIELD AND INDUSTRIAL APPLICABILITY
[0002] The present disclosure relates to a cutting tool insert for
use in earth boring operations, and specifically to a cutting tool
insert capable of providing feedback relating to conditions of the
cutting tool insert itself by way of a sensing device within the
cutting tool insert.
[0003] Earth boring operations are conducted using rotary earth
boring bits mounted at the end of a long shaft that extends into
the hole being bored Earth boring bits typically includes a
plurality of cutting tool inserts having hard cutting surfaces that
can grind into the earth. Several types of earth boring bits are
known; coring bits, roller cone bits and shear cutter bits. The
cutting tool inserts may comprise hard metal, ceramics, or
superhard materials such as diamond or cubic boron nitride.
[0004] During earth boring operations, the working surface of the
inserts may reach temperatures as high as 700.degree. C., even when
cooling measures are employed. It can be appreciated that due to
the high contact pressure between the cutting insert and the earth
formation, that large temperature gradients may exist between the
actual contact point and surfaces remote from the contact point.
The maximum temperature and the gradient may damage the cutting
tool, reducing the economic life of the earth boring bit. To an
operator located remote from the earth boring tool, the condition
of the earth boring cutters may only be inferred from the overall
bit performance.
[0005] There is essentially no direct feedback from the earth
boring bit to indicate wear on the cutting tool inserts, or
conditions that would signal imminent failure of one or more of the
cutting tool inserts. Only after a failure has occurred does an
operator get feedback of a problem, when the earth boring bit
cutting rate decreases, the bit can no longer turn or power must be
increased to cut into the earth. At that point, it is too late to
avoid the costly and time consuming remedial work of withdrawing
the entire shaft and earth boring bit form the hole and repairing
the earth boring bit by removing and replacing failed cutting tool
inserts. It would be preferable to provide a cutting tool insert,
and method of boring using a cutting tool insert that provides the
operator with sufficient information to be able to adjust drilling
parameters such as torque, weight on the bit, and rotational speed
in order to prevent cutting tool failures.
[0006] Therefore, it can be seen there is need for a cutting
element integrated with sensing elements to be used in earth-boring
drilling tool.
SUMMARY
[0007] In one embodiment, a cutting element for earth-boring
drilling tool comprises a substrate, a superhard layer bonded to
the substrate along an interface, the superhard particle layer
having a working surface opposite the interface and an outer
peripheral surface extending between the working surface and the
interface; and a sensing element comprising at least a part of the
superhard layer.
[0008] In another embodiment, a method of making a cutting element
for earth-boring drilling tool, comprises steps of providing a
superhard layer wherein at least a part of superhard layer
comprises a sensing element and transferring means; providing a
substrate; and bonding the substrate to the superhard layer.
[0009] In yet another embodiment, an apparatus comprises a
superhard layer having a working surface and an interface opposite
to the working surface, the superhard layer further comprising an
outer peripheral surface extending between the working surface and
the interface, wherein the superhard layer has a sensing element
and a connector, wherein the sensing element is configured to
generate information relating to the superhard layer and the
connector is configured to send information generated from the
sensing element to a circuit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The foregoing, as well as the following detailed description
of the embodiments, will be better understood when read in
conjunction with the appended drawings. For the purpose of
illustration, there are shown in the drawings some embodiments
which may be preferable. It should be understood, however, that the
embodiments depicted are not limited to the precise arrangements
and instrumentalities shown.
[0011] FIG. 1 is a schematic diagram of a conventional drilling
system which includes a drill string having a fixed cutter drill
bit attached at one end for drilling bore holes through
subterranean earth formations;
[0012] FIG. 2 is a perspective view of a prior art fixed cutter
drill bit;
[0013] FIG. 3A is a schematic cross-sectional view of a cutting
tool insert mounted in a cutter drill bit and having conductors
connected to a substrate of the insert and a superhard material of
the insert so that the insert can serve as a sensing device
according to one exemplary embodiment;
[0014] FIG. 3B is a schematic cross-sectional view of a cutting
tool insert mounted in a cutter drill bit and having conductors
connected to a substrate of the insert and a superhard material of
the insert so that the insert can serve as a sensing device
according to another exemplary embodiment; and
[0015] FIG. 4 is a schematic cross-sectional view of a cutting tool
insert showing electrical, optical or other contacts with the
working surface of the earth boring cutting element according to
yet another exemplary embodiment.
DETAILED DESCRIPTION
[0016] An exemplary embodiment of a cutting element for
earth-boring drilling tool may be made of a substrate, a superhard
layer bonded to the substrate along an interface between the
substrate and the superhard layer. A sensing element may be
operatively interfacing the superhard layer and the substrate. The
sensing element may be used to measure the superhard layer's
temperature, pressure, wear, magnetic properties, wear volume,
force, and combinations thereof, for example. An exemplary
embodiment may further include a transferring means, such as a
connector, for transferring output signals from the sensing element
to a circuit located in the drill bit, which in turn was sent to
the operator above the ground.
[0017] FIG. 1 illustrates one example of a conventional drilling
system for drilling boreholes in subsurface earth formations. Fixed
cutter bits, such as PDC drill bits, are commonly used in the oil
and gas industry to drill well bores. This drilling system includes
a drilling rig 10 used to turn a drill string 12 which extends
downward into a well bore 14. Connected to the end of the drill
string 12 is a fixed cutter drill bit 20.
[0018] As shown in FIG. 2, a fixed cutter drill bit 20 typically
includes a bit body 22 having an externally threaded connection at
one end 24, and a plurality of blades 26 extending from the other
end of bit body 22 and forming the cutting surface of the bit 20. A
plurality of cutting elements 28, such as cutters, may be attached
to each of the blades 26 and extend from the blades to cut through
earth formations when the bit 20 is rotated during drilling.
[0019] The cutting element 28 may deform the earth formation by
scraping and shearing. The cutting element 28 may be a tungsten
carbide insert, or polycrystalline diamond compact, a
polycrystalline diamond insert, milled steel teeth, or any other
materials hard and strong enough to deform or cut through the
formation. Hardfacing (not shown), such as coating, for example,
may also be applied to the cutting element 28 and other portion of
the bit 20 to reduce wear on the bit 20 and to increase the life of
the bit 20 as the bit 20 cuts through earth formations.
[0020] FIGS. 3A and 3B show exemplary embodiments of a cutting
element 28 mounted in the bit 20. The cutting element 28 may
include a substrate 36 and a superhard layer 35 joined at an
interface 18 along on at least one surface of the substrate 36. The
substrate 36 may be made from a hard material such as tungsten
carbide, while the superhard layer 35 may be made from a superhard
material, including but not limited to a polycrystalline diamond, a
composite diamond material, cubic boron nitride, or ceramic,
chemical vapor deposition (CVD) diamond, leached sintered
polycrystalline diamond, for example. The term, composite diamond
material, used herein, refers to any materials combined with
diamond, such as silica carbide, or any ceramics, for example. The
superhard layer 35 may include a working surface 16 that, in
operation, is placed into abrasive contact with the earth. The
working surface 16 may be opposite the interface 18. The superhard
layer 35 may further include an outer peripheral surface 40 which
may extend between the working surface 16 and the interface 18.
[0021] The cutting element 28 may further include a sensing element
50 which may be at least part of the superhard layer 35 or the
substrate 36. The sensing element 50 may be selected from a group
of temperature sensors, pyroelectric sensors, piezoelectric
sensors, magnetic sensors, acoustic sensors, optical sensors,
infrared sensors, electrodes, electrical resistance sensors, and
combinations thereof, for example. The sensing element 50 may be at
least partly located within the superhard layer 35. In another
exemplary embodiment, the sensing element 50 may be at least partly
located or imbedded within the substrate 36, which may comprise a
hard metal, such as tungsten carbide, for example.
[0022] In an exemplary embodiment, the sensing element 50 may a
temperature sensor, such as a thermistor, which comprises a diamond
and cobalt working layer (or surface) which changes resistance as
the working layer of the cutter temperature is increased. In
another embodiment, the diamond and cobalt working layer may be
altered (or doped) to achieve useful electrical properties.
[0023] In other exemplary embodiments, the superhard layer 35 may
comprise compact of a superabrasive with other catalysts or binder
phases (as known) that change resistance as the temperature of the
working layer is increased.
[0024] In yet another exemplary embodiment, the sensing element 50
may be thermal pyrometer comprising a diamond and cobalt working
surface 16 which emits photons as the temperature of the working
layer of the cutting element 28 is increased.
[0025] In further other embodiments, the sensing element 50 may be
a thermoelectric device comprising two regions of diamond with
different doping states.
[0026] In the depicted embodiments of FIGS. 3A and 3B, the cutting
element working surface 16 may itself act as an integral sensing
device such as a resistance thermocouple, strain sensor, optical
emitter, A transferring means, such as a connector 38, may be
attached to the superhard layer 35, and another transferring means,
such as a connector 38, may be attached to the substrate 36 to
extract sensor information.
[0027] Still in FIGS. 3A and 3B, the thermistor may be integrated
with the working layer 16 and the resistance change may be detected
by two electrodes extending into the working layer. The conductors
may be doped diamond, conductive cBN materials, conductive
refractory metals or their compounds. These electrodes may extend
through the substrate 36 and may be insulated from the substrate by
nonconductive materials such as oxides, glass, nonconductive
diamond or cBN or other non-conductors. As the temperature of the
cutting element 28 increases, its resistance increases, and the
increase in resistance may be measured between a connector attached
to the substrate 36 and another connector attached to the superhard
layer 35. To refine the calibration of the resistance, one or both
of the substrate 36 and the superhard layer 35 may be modified (or
doped) with a resistance element. Thermoelectric elements may also
be made from polycrystalline diamond (PCD) which forms part or the
entire superhard layer 35. Alternatively, optical sensors,
utilizing the diamond as an emitter element, may be used to measure
temperature at different surfaces of the cutting element 28.
[0028] One exemplary embodiment may be the integral thermistor that
may be placed in the cutting element 28 so the
temperature-measuring region essentially coincides with the cutting
surface 16. The thermistor itself may be then worn as the superhard
layer 35 is worn. At the wear front, the two leads of the
thermocouple are continually welded together due to the force and
frictional heat of cutting, so that temperature may continue to be
monitored even as the thermocouple itself wears away. Also, changes
in resistance, including infinite resistance, may be used to
quantify wear and tear.
[0029] In another exemplary embodiment, the integral working layer
sensing element 50 may act as a pyro electric or a piezoelectric
sensor. These sensors may be used to measure vibration, impulse
force, or machine chatter, which are indications of the amount of
force or load being applied to the cutting element 28. These
sensors may also be used to determine volume changes in the insert
(e.g., due to phase change as a result of loss of volume from
erosion or wearing away of the insert).
[0030] Acoustic or ultrasonic integral sensors comprising the
working layer or surface may be used to measure vibration, volume
changes, and even location of the cutting element 28 in the hole.
An acoustic or ultrasound sensor may also be used to detect
imminent or actual cracks in the cutting element 28.
[0031] In a further exemplary embodiment, the sensing element 50
may be an integral capacitance sensor to detect capacitance or
capacitive losses from inside or from the surface of the insert.
Capacitance may be used to provide information about wear of the
cutting element 28.
[0032] In another exemplary embodiment, an active sensing element
may be incorporated in a leached diamond working surface. It is
well-known in the art to remove or partially remove catalytic metal
phase from the near surface of a diamond cutting insert. In this
example the removed catalytic metal, normally Cobalt, for example,
may be replaced with another material with advantages as a sensor.
For example, the cobalt may be replaced with gold which has a
higher thermal coefficient of resistance and may increase the
sensitivity of the integral thermistor. The conductive paths may
extend sufficiently to reach this modified layer.
[0033] In another exemplary embodiment, a different type of active
sensor element may be incorporated in a leached diamond working
surface. In this embodiment, the removed catalytic metal, normally
cobalt, is replaced with two different materials each in discrete
areas of the working surface with a common area or junction to form
a thermoelectric element. For example, the cobalt may be replaced
with a nickel chromium alloy in one region and a nickel manganese
alloy in a second region with a common interface to create the
thermoelectric element. Other thermoelectric material combinations
are possible to obtain the needed temperature sensitivity, magnetic
properties, or corrosion resistance. The conductive paths may now
extend sufficiently to reach these modified layers.
[0034] In another exemplary embodiment, integral optical sensors
comprising an optical interferometer that may be used to detect the
deformation of a cutting tool insert, which may be an indication of
wear, shear force, and normal force on the insert. Alternatively, a
discrete optical transducer can be incorporated in the cutter. The
discrete optical transducer may comprise a material having an index
of refraction that changes with temperature, such as Lithium
Niobate. This discrete sensor may be a part of the cutting element,
but not composed of the same material as the cutter working
surface. Optical interferometry may then be carried out with such a
transducer using a laser to measure an index of refraction through
the material.
[0035] In another example, two Raman peaks of positively-charged
Erbium ions (Er.sup.+3) may be compared, and the ratio of
intensities correlated with temperature. A carrier for the Erbium
may be made from AlN, AlGaN, or Cr, any of which provides good
thermal conductivity for the Er.sup.+3 ions. The integral
electrical or optical sensor may be incorporated in the working
layer, by replacing the catalyst metal with the electrically or
optically active phase.
[0036] In addition, multiple integral sensors may be employed at
different locations on a single insert, or on a plurality of
inserts on the same boring bit, to detect gradients in temperature,
pressure, force, deformation, vibration, and any other parameter
that may be measured by the sensors. In particular, by mounting
force-detecting sensors on multiple inserts, shear and normal
forces across the boring bit may be determined.
[0037] While sensors integrated to the working surface, may provide
information about cutter conditions, as discussed above, it is
envisioned that one or more cutting element may be employed as
sacrificial or performance-measuring inserts. For example, a
compromised cutting element may be prepared by cutting or slicing
the body of the insert and then back filling the cuts or slices
with material and/or sensors. The body can be sliced partially or
completely in an axial or radial direction, which allows for
electrical or force separation between parts on opposite sides of a
slice (i.e., forming a P-N junction or a piezoelectric
sandwich).
[0038] Alternatively, a sacrificial insert may be formed entirely
of a substrate material such as tungsten carbide, without a
superhard layer to form a cutting surface. Such an insert is easier
to form than an insert having a superhard layer, since the
superhard material is typically formed and fused to the substrate
in a high-temperature high-pressure process that may be too extreme
for some sensors to survive. The sacrificial insert can be placed
in the cutting "shadow" of another insert to provide information on
wear, mud conditions, force, and other parameters, but cannot
provide cutting edge temperatures of the other insert.
[0039] In operation, when both connectors 38 are connected to a
circuit (not shown) in the drilling bit 20, in one exemplary
embodiment, under a pre-determined voltage, current may flow from a
first connector 38 through the sensing element 50, which comprises
conductive materials, such as cobalt, in at least part of the
superhard layer, then cross the interface 18, to the sensing
element, which comprises conductive materials, such as cobalt,
tungsten, in at least part of the substrate 36, finally to a second
connector 38. Information, such as resistance, may be calculated
via dividing the pre-determined voltage by detected current, for
example.
[0040] When cutting element 28 abrades rocks of earth formation,
heat is generated. As superhard layer temperature increases,
properties of the superhard layer changes, such as resistance. A
change of resistance may be sensed by the circuit in the drilling
bit 20, which in turn may be sent to an operator above the
ground.
[0041] In another exemplary embodiment, current may flow from a
second connector 38 through the sensing element 50, which comprises
conductive materials, such as cobalt, tungsten, in at least a part
of the substrate 36, then flow across the interface 18, to the
sensing element in at least part of the substrate 35, then finally
to a second connector 38.
[0042] FIG. 4 shows another exemplary embodiment of a cutting
element 28 having two electrical or optical pathways 34 mounted
therein. The sensing element 50 may comprise a portion of the
superhard layer 35. In the depicted embodiment, the pathways 30 may
be mounted in apertures 32 bored into the rear side of the
substrate 32 of the insert 28. The pathways 34 to extract sensing
response may extend into an interior portion of the substrate 36
close to the interface 18 between the substrate 36 and the
superhard layer 35. To further increase the accuracy of the sensing
element 50 in detecting conditions at or near the cutting surface
16, conductive or optical pathways 34 in the superhard layer 35 may
be provided to extend beyond the interface 18 and an end of the
insulating or passive material of substrate 36.
[0043] An exemplary embodiment of the sensing element 50 may be an
integral sensor that utilizes the superhard layer 35 metal phases
as an active part of the thermoelectric device. For instance if the
binder phase were to consist of pure Cobalt, the thermal resistance
coefficient may be used to measure the temperature between wires
inside passage way 34 extending into the superhard layer 35.
[0044] It may also be possible to create a thermoelectric element
from most dissimilar materials. An example may be producing a
thermoelectric element of diamond and boron compounds; diamond and
refractor metals; or doped Silicon carbide conductors and
diamond.
[0045] Still in FIG. 4, an exemplary embodiment of another such
sensing element may be to use optical fibers inside passage way 34
to carry out optical pyrometer using diamond in the superhard layer
35 as a photon emitter to measure the infrared emission of the
metal binder or diamond. An example of another sensor might be to
use optical fibers in the passage ways 34 to measure the Raman
shift of Diamond in the superhard layer 35. This would reveal
stress or strain of the superhard layer 35.
[0046] With multiple electrical, optical, or capacitive contacts to
the superhard layer, an array of sensors may be used. These arrays
of sensors may be used to collect more information or, as cutter
wear destroys the array PCD sensing elements, a quantitative
description of cutter wear may be obtained.
[0047] Regardless the configuration, one or more sensing element 50
may be selected from a wide range of sensors to measure different
parameters that provide various types of information regarding the
status of the cutting element 28. The sensing element 28 may be
used to generate information relating to the superhard layer 35.
Each sensing element 50 may include one or more sensors for
detecting operational parameters capable of indicating the state of
the cutting element 28.
[0048] By detecting such parameters, it may be determined whether
the cutting operation is being conducted too aggressively, which
may risk failure of the cutting element 28, or too conservatively,
which may result in longer boring times than necessary. For
example, monitoring the temperature of the working surface of the
cutting element 28 near the cutting surface 16 enables an operator
to detect wear to the superhard layer 35 so that drilling
parameters, such as torque, weight on the bit (WOB), and rotational
speed (RPM), may be adjusted to avoid tool failure. Rising
temperature is a particularly strong indicator of impending tool
failure because increased temperature at the cutting surface 16 may
signal increased friction, which further increases temperature
until the superhard layer 35 ultimately may be delaminated from the
substrate 36 or the superhard layer 35 may reach such a high
coefficient of friction that the drilling bit grinds to a halt.
[0049] An earth boring diamond (PCD) cutter as shown in FIG. 4 may
be produced with an integral thermistor. Diamond particles are
placed in a 14 mm diameter by 10 mm tall tantalum container to a
depth up to about 4 mm. A hard metal substrate with through vias is
placed in the same tantalum cup. Aluminum oxide tubing and tantalum
electrodes are placed in the vias so that the tantalum metal
electrode and aluminum oxide sleeve penetrate into the diamond
powder layer about 1 mm. A second tantalum cup is placed over the
rear of the assembly. The cup, diamond powder, hard metal
substrate, insulators, and electrode assembly is sintered at
pressure of over 50 kbar and over 1300.degree. C. to form sintered
diamond layer and integral substrate with electrodes. After
sintering the tantalum cups are ground away to create a
conventional 13 mm by 8 mm tall cutting insert with a 2 mm diamond
layer. The distal (to the working surface) end of the substrate may
be ground to expose the tantalum electrodes. The integral sensor
exposed to increasing temperatures and the resistance response is
measured between the exposed electrodes for calibration purposes.
The earth boring PCD cutter, with the integral thermistor is
incorporated in an earth boring bit that comprises connectors, data
collection, data storage, and telemetry capability to allow
transmission of the temperature information to the drill rig
operator.
[0050] An earth boring diamond (PCD) cutter as shown in FIG. 4 may
be produced with an integral optical emitter for temperature
measurement. Diamond particles are placed in a 14 mm diameter by 10
mm tall tantalum container to a depth up to about 4 mm. A hard
metal substrate with at least one through via is placed in the same
tantalum cup. A transparent optical pathway, examples being
sapphire or quartz, diamond, or fused silica, or a hole, is placed
in the vias so that the transparent pathway penetrates into the
diamond powder layer about 1 mm.
[0051] A second tantalum cup is placed over the rear of the
assembly. The cup, diamond powder, hard metal substrate, and
optical pathway are sintered at pressure of over 50 kbar and over
1300.degree. C. to form a sintered diamond layer and integral
substrate with an optical pathway. After sintering, the tantalum
cups are ground away to create a conventional 13 mm by 8 mm tall
cutting insert with a 2 mm diamond layer. The distal (to the
working surface) end of the substrate is ground to expose the
optical pathway. The diamond emitter is exposed to increasing
temperatures and optical emission at the distal end of the cutter
is measured for calibration purposes. The earth boring PCD cut,
with the integral optical emitter is incorporated in an earth
boring bit that comprises optical sensing, data collection, data
storage, and telemetry capability to allow transmission of the
temperature information to the drill rig operator.
[0052] While reference has been made to specific embodiments, it is
apparent that other embodiments and variations can be devised by
others skilled in the art without departing from their spirit and
scope. The appended claims are intended to be construed to include
all such embodiments and equivalent variations.
* * * * *